package com.hdu.point_offer;

import java.util.LinkedHashMap;

public class lcr169 {
    class Solution {
        public char dismantlingAction(String arr)
        {
            LinkedHashMap<Character, Integer> map = new LinkedHashMap<>();
            for (int i = 0; i < arr.length(); i++)
            {
                map.put(arr.charAt(i), map.getOrDefault(arr.charAt(i), 0) + 1);
            }
            for (char key : map.keySet())
            {
                if (map.get(key) == 1)
                {
                    return key;
                }
            }
            return ' ';
        }
    }
}
